code segment
   assume cs:code
start:  
    mov bx,0a9b6h
    mov ch,4
    mov cl,4
p3: rol bx,cl
    mov dl,bl
    and dl,0fh
    cmp dl,09h
    jle p1
    add dl,37h
    jmp short p2

p1: add dl,30h
p2: mov ah,2
    int 21h ; 输出dl
    dec ch
    jnz p3
    mov dl,'H'
    mov ah,2
    int 21h
    mov ah,4ch
    int 21h

code ends
end start
